Nucleate boiling heat transfer of binary mixtures at low to moderate heat fluxes

A model for nucleate pool boiling hear transfer of binary mixtures has been proposed based on an additive mechanism. The contributing modes of heat tr ansfer are (i) the heat transferred by microlayer evaporation, (ii) the hea t transferred by transient conduction during the reformation of the thermal boundary layer, and (iii) the heat transferred by turbulent natural convec tion. The model takes into account the microroughnness of the heating surfa ce which has been defined quantitatively. The model compares satisfactorily with data obtained in the present study and in the literature. These data were obtained on a variety of heating surfaces such as a vertical platinum wire, a horizontal stainless steel tube and flat horizontal aluminium, and stainless steel surfaces (with various surface finishes) thereby demonstrat ing the validity of the model.